Effects of extreme ‘heat dome’ will be felt in Orange County through Monday night

Close the windows, crank up the air and stay hydrated — a massive ridge of high pressure has created a “heat dome” that will burden coastal and inland Orange County with exceedingly high temperatures and humid conditions into next week.

In an excessive heat warning issued Tuesday, National Weather Service meteorologists cautioned dangerously hot conditions would continue at least through Monday night as temperatures soared into the upper 80s in coastal areas and well into the 90s immediately inland.

“There is a big ridge of high pressure sitting over the Great Basin right now — in Nevada, Arizona, Idaho and Utah — that is basically going to lead to mostly clear skies, which will lead to skyrocketing temperatures throughout the Southwest region,” NWS meteorologist Elizabeth Schenk said Wednesday, indicating heat warnings extend into the Pacific Northwest.

Locals beat the heat at the Newport Dunes Wednesday after the National Weather Service issued an excessive heat advisory for Orange County anticipated to last through Labor Day.

(Don Leach / Staff Photographer)

“It’s a very large-scale event,” she added. “It’s been brewing for days.”

Along with heat, high levels of humidity will make daytime highs feel even hotter, while overnight lows will remain in the 70s for the next week, officials reported.

Forecasts indicate inland communities, including Santa Ana, Anaheim, Irvine and Orange, could experience triple-digit temperatures over the weekend before a slight cooling trend brings the mercury down slightly by Wednesday or Thursday of next week.

Extreme heat increases the potential for heat-related illness, ranging from exhaustion to heat stroke, particularly for people working outdoors or participating in outdoor activities, according to the National Weather Service. Residents are asked to monitor their own risk and symptoms and to check on sensitive groups, including children, the elderly and immunocompromised individuals.

Orange County has released a list of cooling centers, mainly libraries, community and senior centers open during hours when locals can escape daily high temperatures.

Paddleboarders at the Newport Dunes Waterfront Resort Wednesday, two days into a heatwave expected to bring extreme conditions through Monday.

(Don Leach / Staff Photographer)

Meanwhile, coastal cities and destinations are gearing up for an influx of visitors and heat refugees from areas like the Inland Empire, where cities like Riverside are expected to see 111 degrees this weekend.

The Newport Dunes Waterfront Resort and Marina is one such refuge. Jan Yerzik, a spokesman for the facility, said Wednesday activities like pedal boating, kayaking and paddle boarding are swiftly booking up as more people seek to escape the heat.

An on-site water park offers inflatable slides, trampolines and other kid-friendly adventures that allow resort members and the general public can cool down in the calm waters of Newport’s Back Bay for an hourly fee.

“It’s just a fun activity and it gets you out on the water, and kids get a good workout,” she said, adding that trees on the property offer a good escape from the sun. “It’s going to be a very busy weekend for us — bring your floats and come float in the water.”

Schenk said coastal areas may be periodically protected from the worst of the impacts if the marine layer lingers, although high dewpoint levels in the 60% to 70% range will lend an uncomfortable, “sticky” feeling verging on tropical. It will be important, she said, to limit outdoor activities to the morning or evening and stay aware of how you feel.

“Ask, am I feeling lightheaded? Am I feeling dizzy? Do I need to take a break?” the meteorologist advised. “Make sure you’re checking on yourself and others.”

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